Tubing



Nov. 7, 1939f H. H. HENRY ,935

TUBING Filed Oct. 17, 1936 Patented Nov. 7, 1939 UNHEE TATES TUBING Harry H. Henry, Chicago,

111., assignor to Eattery Patents Corporation, Chicago, 111., a corporation of Illinois Application October 17, 1936, Serial No. 106,239

4 Claims.

This invention relates to tubing, and also to tubing formed into a bicycle handle bar and the like.

An object of the invention is to provide tubing formed in a novel shape and designed for increasing the strength thereof. A further object is to provide a handle bar and the like of novel construction which resists turning and which is extremely sturdy in construction. Other specific objects and advantages will appear as the specification proceeds.

The invention is described, in a preferred embodiment, by the accompanying drawing in which Figure 1 is a broken plan view of a portion of tubing constituting part of a blank which is to be formed into a bicycle handle bar; Fig. 2, a top plan view of the complete handle bar secured to the steering post of a bicycle; Fig. 3, a broken sectional view, the section being taken as indicated at line 3 of Fig. 2; and Fig. 4, a transverse sectional view, the section being taken as indicated at line 4 of Fig. 1.

In the illustration given, the steering post A is provided with a rearwardly extending portion A providing a hexagonal socket ii]. The lower portion of the socket portion It is split to form a clamp, the split portions being connected by a bolt 1 I.

The handle bar B is provided with an enlarged central portion l2, hexagonal in shape and received within the portion A.

The handle bar B has its portions on both sides of the enlarged area I?! tapering inwardly at l3. Beyond the tapered portions 53, the arms M are of substantially uniform diameter. The reduced portions Ill have the configuration in cross section shown in Fig. 4. It will be noted that there are six sides in which alternating sides are convex and concave, the concave sides being designated by the numeral l5 and the convex sides being designated by the numeral iii. This cross sectional structure renders the tubing extremely sturdy. Tests show that by changing the shape of the original hexagonal tube to the shape shown in Fig. 1, the strength of the tube is increased from 50 to 100 per cent.

The process of producing the tube in its finished form is as follows: The first step consists in forming an hexagonal tube of the shape illustrated by the portion ii in Figs. 1, 2 and 3. In other words, the tube is made substantially throughout like portion l2. This may be accomplished in an extruding device having a central of a swaging machine socket ill of the steering post mandrel or core. In the extruding operation, at least one of the sides I5 is found to be weaker than the other sides. In other words, it is practically impossible to make all of the sides alike in cross sectional strength. One end of the hexagonal tube thus produced is pressed into the end and the cross sectional area of the tube is reduced from that shown at IE to that shown at M. The eifect of the swaging is to cause some of the sides to become convex and others to become concave. The fact that one side is weaker than an adjacent side causes the sides to assume opposite bulging positions, one being concave and the other convex.

Since the weakness in one side exists throughout the entire length of the tube, because the tube is formed in an extruding device, the concave sides It and convex sides It are aligned on opposite sides of the portion l2. In other words, the concave sides l5 are the same on one side of the handle bar as on the other, and the same is true of the sides l6. It will be noted that the swaging operation produces a tapered formation at I3 in which the degree of bulging inwardly and outwardly of the sides is reduced.

It will be understood, of course, that the entire handle bar may be reduced in cross section to the configuration shown in Fig. 4. The form illustrated, however, is preferred because the central portion is hexagonal and fits snugly within the socket II).

It will be understood that the tube may be formed of any number of sides. While I prefer to have a tube with an even number of sides so that the concave sides will be alternating with the convex sides, it will be understood that an uneven number may be used, in which case there will have to be two sides of the same configuration adjacent each other.

If desired, each alternate side in an equal sided tube may be weakened by making a slight change in the extruding die. It has been found, however, that when a single side is weakened, the entire tube, when swaged, assumes the shape in which concave sides alternate with convex sides. result is the same, no matter which end of the tube is inserted .into the swaging device.

The operation is extremely simple and results in a product of much increased strength.

While in the foregoing description, we have shown the invention applicable to tubes generally, and more specifically to a handle bar, it will be understood that the tubing is especially adapted for use in a bicycle frame for the connection of the head cluster and hanger members, and also The for frame construction in other vehicles and devices.

The foregoing detailed description has been given for clearness of understanding only, and no unnecessary limitations should be understood therefrom, but the appended claims should be construed as broadly as permissible, in view of the prior art.

I claim:

1. A bicycle handle bar comprising a polygonal tube having its end portions reduced in cross section and having at least one side of the reduced portion convex and an adjacent side concave.

2. A handle bar comprising a polygonal tube having an enlarged central portion and reduced end portions, said end portions having alternating convex and concave sides.

3. In combination with a cycle steering post provided with a socket in the shape of a regular polygon, a handle bar having an even number of sides fitting said socket, and clamping means for securing said bar within said socket,- said handle bar having its end portions provided with alternating convex and concave sides.

4. In combination with a cycle steering post provided with a socket in the shape of a hexagon, a hexagonal handle bar fitting said socket, and clamping means for securing said bar within said socket, said handle bar having its end portions reduced in cross section and provided with alternating convex and concave sides.

HARRY H. HENRY. 

